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Frak - maybe best to start a new thread about dyno graph's - we have moved on from talking about cams plus I will add my graph which should be good indication of boosted 4A. Call the thread - "Frak talking the thruth - do not add useless shit to this thread"

Any basic after market computer will run small cams as there isn't a great deal of difficulty. Once the duration is increased you start having more issues with idle and fuelling (due to overlap and MAP issues as Frak said) and a better computer is necessary. Adding quad to cams is aftermarket computer necessary.

You will get MORE power with aftermarket computer over a stock computer but if all you have is 264's, thin head gasket, stick with stock computer. I ran this for years and never an issue. Little lean on JDM AE86 computer but never any problems.

An indication:
4AG bigport, 0.5mm TRD head gasket, head de-dagged and cleaned up, slightly shaved to clean it up. 263 8.35mm inlet cam, 240 ex. 77rwkw on dyno dynamic. JDM AE86 early ECU, 4-2-1 extractors. No noticable loss down low. Once I went to a 264 8.35 exh, still no noticable loss down (like any atmo 4A has bottom end) but would pull super clean to redline. Would have benefited from going to 100kw ECU as it would have been nice to rev it out to 8K, always use to run it just before the limiter when out on the track. Another 600 rpm would have nice.

I have taken off the top of the dyno sheets as I don't want the owners details etc to be posted up.

BUT let me assure you, these are all legit, done by the same operator(me ) and using the same correction factor etc etc etc The dyno used is a Mainline.
I really don't want to hear comments about dyno accuracy, if these are all done on the same dyno by the same operator then we can all say the testing etc was the same

There has been a reason I typed all the other stuff previously about the operation of the dyno, so that when less experienced forum members saw the figures, it would make sense to them.

This is also the reason I have printed out DERIVED torque curves, so it sort of makes more sense to guys not use to seeing dyno runs, that and I don't have to put up with fuckwits making comments that a 16v bigport had 250NM of torque.

Please note that ALL the runs have been mapped over RPM(bottom axis) so ignore the road speed and just look at the rpm.

Also sorry for random hair on some scans(was on my scanner) no smart comments it's obvious it's from my head

This is a bigport with what I call typical low cost mods;
Pod filter
4-1's and larger exhaust(2 1/4)
This is very typical of a near std 16v bigport, on our dyno they usually get between 60-66kw depending on engine condition, typical a/f ratio, this one gets a little rich above 5900rpm, torque curve is fairly flat, this would be nice to drive on the road.

The second set of runs were a car which was powered by a bigport, 264deg inlet and exhaust cams, 4-1's, JDM cat back, lightweight flywheel
a/f ratio on this is quite good, a little lean between 4800-5800rpm, with a corresponding dip in torque at that point, richening it up could smooth that a little, this produced good power considering mods, torque is quite soft below4400rpm, maybe some fettling of the cams could of helped, typical of 16v's it's all over before the rev limiter.

This set of runs is a ST running stock ecu/afm, pod filter, genie headers but 2 1/4 exhaust
The a/f ratio on this 20v ST was a little on the rich side, power output was as expected and the torque curve is very nice, this has quite a wide torque band and if you compare to the 16v's much nicer, typical of ST's it shuts down well before the rev limiter.

This set are from a standard low km BT, which had the ignition timing optimised, royal purple oil, redline transaxle oil etc.
As you can see the BT definately delivers the goods, the a/f ratio is quite good BUT the torque curve is not the nicest, even tho the torque is much more than the 16v's it has a substantial dip at 4800rpm, what is funny is that even with this dip the torque is still more than some modded 16v peak torque figures, anyway, the down side to this dip is this car feels wanting below 5000rpm, this is the magically rpm figure you are all ways waiting for/looking for! What is nice about the BT is the way it keeps producing good power to rev limiter, above 5000rpm the BT is a great engine, standard THE best 4age.

This set of runs are from a 16v small port, 100kw MAP ecu, AE111 quads and velocity stacks, 4-2-1 headers, 2 inch exhaust, 264 HKS inlet/exhaust cams and optimised cam timing via vernier sprockets, TRD thin head gasket, light weight flywheel
This engine put out the goods, I was not expecting this output with these mods, it did take about 2 hours of messing with cam timing to get an engine which was razor sharp(everywhere, off idle, low rpm, mid and high rpm) and revved cleanly, a/f ratio on stock ecu is suprisingly good, I even checked throughout the rpm range at different engine loads and it was good. What a fantastic torque curve, this is the sort of torque curve you boys that do hills runs want, no nasty suprises, just nice torque everywhere, you can see that even with cams etc etc typical of 16v it shuts down before rpm limit(obviously bigger cams/head work would alleviate this) But overall this is the sort of 16v engine that would do as a nice daily and still have some fun in the hills and do a few sprints at the track.

Just for comparison I thought I'd throw in what everyone on the internet reckons is the best NA 1.6ltr engine made, the Honda B16 vtec, this one was fitted with pod filter and cat back JDM exhaust.
This suprised me in that I was expecting alot more from this so called legendary engine, don't get me wrong, it sounded balistic and 86kw is nothing to sneeze at, but I just thought it would deliver more, when you overlay the BT torque curve the BT kills it EVERYWHERE. But having said that, it's still an excellent output from what is basically a standard 1.6 ltr NA engine.

The BT is completely standard except for altering the ignition timing, good oil, new filters etc, that's with the VVT, which suprised me as a ST doesn't act that way(very minor dip), that BT(belongs to me, it's my daily driver) is now fitted with I.Mec short rams and picked up 6kw at the wheels BUT it makes the dip feel like a chasm! BUT above 5000rpm it really get's going as would expect of an NA with just over 100kw at the wheels!

But for sure Sam, I think it shows just how strong a BT is.

I do have a run of a ST with an aftermarket ecu, short stacks, 4-1's but it's not on this dyno(it's on an engine dyno) so it's a little hard to compare. This ST put out flywheel 127kw@7500rpm and 172NM@6500rpm of torque.

Yes I have them in higher res or if you PM you address I'll just mail you the printouts

I was actually a little disappointed with the Honda, don't get me wrong, it's a wicked output for an NA 1.6 BUT I just thought it would deliver more, I really expected into the mid 90kw's.

I was quite suprised by how linear the power curve was on the B16, I would of thought it would be been much more peaky considering the nature of the VTEC system.

Just on Sam's comment, a linear power curve is a dead give away that the engine has a flat torque curve, compare a power/torque curve of an engine with a flat torque curve and one with dips etc(BT) and check the shape of the power curve.

Now some people like an engine that feels peaky, ie, the torque curve is not flat, they feel this adds to the excitement.

An engine with a flat torque curve can feel boring, but when you look at the speedo or look at where you just came from you will be suprised, an engine with a flat torque curve will be easier to drive on the limit, no nasty suprises from dramatically increasing/decreasing torque!

Nowadays manufacturers try very hard to make an engine that delivers a very flat torque curve.

I will be running the same (HKS 264 8.1 cams, Quads, 4-2-1 headers, adj cam gears, etc) as above with addition of an Aftermarket ECU (Microtech LT10s), GZE injectors and 2.25" exhaust, also I have smallport bottom end and bigport top. I will not have a lightened flywheel yet though.

Reckon I'll see much more increase over the results you posted?

I'd love to get an extra 10rwkw from the difference I will be running to hit 100rwkw, would like to hear some thoughts based on Fraks results / other previous experience.

very interesting indeed. I tottaly agree with you on the power delivery vs feel. I had the exact same experience myself. It reminds me of a story I was told about a guy at the Wolf ECU HQ, he had a guy with a big turbo on his engine, very peaky and all that was to get a retune. With the new tune it gained a huge amount of mid range power and the guy actually came back and asked for everything to be undone as the car was boring to drive. But your right, its only for a buzz in a straight line, I will pick the flat torque curve every time also.

Oh and I forgot to mention earlier, good job on working out the torque multiplication factors. I tried to explain to a friend how two cars with the same torque figure but one producing it at twice the revs geared to have the same rotating speed would end up with double the torque. I believe he just ended up with a headache but then again I am not the best at explaining things.

Heres one for you:

now as we both know the figures can't be compared because what I went on would very likely of been a more generous dyno. I wanted to hear any general comments you have and what you make of my huge dip that I have late in my rev range. I was thinking a primary resonace in my intake at about 6000rpm and a secondary resonance in my exhuast at 5000RPM or so.